Method of making carpet grippers



P 1961 R. H. SELSTAD 3,000,009

METHOD OF MAKING CARPET GRIPPERS Filed Sept. 28, 1959 nvvewroe RICHARD H. 5545740 5) HA5 ATTOEA/EYS HARE/5, A7501, RUSSELL c2 KEEN United States Patent Q .r v. METHOD OF MAKING CARPET GRIPPERS RichaId H, Selstad, West Covina, Calif., assignor to The Roberts (10., a corporationof California Filed Sept. 28, 1959, Ser. No; 842,705

' 4 Claims. (Cl. 1*82) 1 Ihisiinvcntionrelates to amethod of making a-carpet zs g'ripper strip useful-- inthe laying of carpet.

A conventional method of making such a-carget gripper "-strip; as. generally disclosed in'PatentNo. 2,752,597, is- "sued to S. I Kent on-July,3, l956;includesdriving each 1 nail to its final. position -in the wooden base strip-and then-forming apoint on the projectingend. This has the primary disadvantage thatduringthe final forming qoperation the nail tends to become loosened in-the strip swam the nail will not sustainthe pulling forces-commonly exerted on it by carpet applied during" the carpet --laying-,operation. 'Also,':this conventional method frequently forms undesirable metal burrs onthe outermost end-of the nail; which tend 'to'tear carpet-later. applied thereto.

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= FIGS, 2 and 3. The-nails12 may be so preformed by any'suitable'rnechanism, such-asshearing dies, which are not shown, but which are no part of the present invention. -Normally, such shearing dies form metal burrs along the outer edges of the surfaces 22, 23,- 24, and

/ 25. --Such burrs are of no importance so far asdriving the nails into a wooden base is concerned. Such burrs onthe'-lower'surfaces"24 and 25 are desirable; as -they aid-in holding the nailin the wooden base strip -11-'and --ing powenof the nail on' the carpet.

The preformed nail -12 is then partially driven i into the base strip 11,--so t-h-at the axis of the nail is at an acute "angle to the upper surface of the strip to a first position 1 such as-shown-in FIG.- 5, in which the nail penetrates not over 35% ofthe thickness of-r-the base strip. In thisini- A primary object of this invention -is-to obviate the foregoing disadvantages of conventional methods by preforming eachhailfdrivingit par'tially into the wooden ---base-str-ip, and then finally forming the exposed point -to eliminate metal burrs and completing the driving of tial-driving .operation,- the'nail is driven into the-base strip only far enough to embed it firmly but no further than required-toso embed it.

--the;pointtoprovide fiat side surfaces 27-and 28 and to remove any burrs; along the outerthinedges of the'surfaces 22 and-23. During this forming step the nail 12 tends to loo's'en'sorn'ewhat from its hold in the base strip "-final' forming of 'theexposed point may be" done" very '1 simply to eliminate metal burrs therefrom and to form a sharper point.

Other objects and advantages will appear from the following specification and the drawing, which are for the purpose of illustration only, and in which:

FIG. 1 is a perspective view, partly in section, showing a carpet gripper strip of this invention attached to a floor and holding a piece of carpet in position;

FIG. 2 is an enlarged elevational end view of one of the nails of this invention after preforming the same;

FIG. 3 is a side view of the nail shown in FIG. 2;

FIG. 4 is a view similar to FIG. 2 but showing the nail after its final forming;

FIG. 5 is a sectional elevational view of a nail after the first driving step of the invention; and

FIG. 6 is a View similar to FIG. 5 but illustrating the nail in the strip after the final forming and driving thereof.

Referring to the drawing, FIG. 1 shows a portion of a carpet gripper 10 having a long narrow base strip 11, preferably formed of plywood, with a plurality of carpet nails 12 projecting upwardly therefrom, the carpet gripper being fixed to a floor 13 adjacent a wall 14 by a nail 15 or other suitable means. A carpet pad 16 is positioned on the floor 13 adjacent the carpet gripper 10 and a carpet 17 rests on the pad with the edges of the carpet engaging the nails 12, the extreme edge 18 of the carpet being tucked over between the carpet gripper and the wall.

Each of the carpet nails 12 is initially preformed to the form shown in FIGS. 2 and 3, the nail being preformed of conventional cylindrical steel wire to have upper and lower faces 20 and 21 which are generally parallel, each being oblique to the longitudinal axis of the nail. Each of the faces 20 and 21 is V-shaped, the upper face 20 being formed of surfaces 22 and 23, and the lower face 21 being similarly formed of surfaces 24 and 25. The junctures of the surfaces 22, 23, 24, and 25 with the body of the nail are arcuate, as shown in 11. "In its final desired form the nail has a sharp 'ex- The nail 12 is then driven to its final position as shown in FIG. 6, in which its lower end is close to, but preferably does not penetrate, the lower surface of the base strip 11. Since the nail 12 has been completely formed before such final driving step, when driven to its final position the nail will be tightly held by the new wood penetrated in the final driving step. Any original burrs on the surfaces 24 and 25 will then assist in retaining the nail in such final position and will resist withdrawal of the nail from the wood due to pulling forces applied to the exposed end by carpet being laid thereon.

As will be understood, the nails 12 may be formed and driven sequentially, by merely advancing the base strip 11 from station to station past suitable forming and driving dies and equipment.

In the past, carpet gripper has been made conventionally by forming the nails with points on both ends and driving them entirely through the wooden base strip so that the lower pointed end of the nail projects slightly therefrom, but in such practice it has been necessary to crimp over the projected point to provide adequate holding strength and to eliminate the projecting points which would be hazardous to the user and would prevent the carpet gripper from being laid flat on a supporting surface. By the method of the present invention, the nails need not be driven entirely through the base strip, which eliminates an extra operation and retains the lower surface of the carpet gripper unmarred by projecting points. Also, by the method of the invention a bond is formed between the nails 12 and the base strip 11 which is sufiiciently strong to prevent removal or loosening of the nails under any normal conditions of use of the carpet gripper.

I desire to be afforded the full scope of the following claims.

I claim as my invention:

1. A method of forming a carpet gripper, including the steps of:

providing a carpet nail comprising a length of metal nail wire having a bevelled face on each end, said faces being parallel and forming points at each end of the I nail;

inserting said bottom end of the nail into a wooden strip through the top surface thereof a distance substantially less than the thickness of the strip and so that the axis of the nail is at an acute angle to the upper surface of the strip;

reforming the point on the upper end form a sharper point; and

driving the nail farther into the strip to a position in which the bottom point of the nail is adjacent to the lower surface of the strip but does not penetrate the same.

2. A method of forming a carpet gripper, including the steps of: a 1

i providing a carpet nail comprising a length of metal nail Wire having a bevelled face on each end, said faces being parallel and forming points at each end of the nail with rough metal burrs adjacent said points;

inserting said bottom end of the nail into a wooden strip through the top surface thereof a distance substantially less than the thickness of the strip and so that the of the nail to inserting said bottom end of the nail into a wooden strip through the top surface thereof a distance less than 35% of the thickness of the strip and so that the axis of the nail is at an acute angle to the upper surface of the strip;

reforming the point on the upper end of the nail to form a sharper point; and

driving the nail farther into the strip into a position in which the bottom point of the nail is adjacent to the lower surface of the strip but does not penetrate the same.

4. A method of forming a carpet gripper, including the steps of:

providing a carpet nail comprising a length of metal nail wire having a bevelled face on each end, said faces being parallel and forming points at each end of the nail; inserting said bottom end of the nail into a wooden strip through the top surface thereof a distance substantially less than the thickness of the strip and so that the axis of the nail is at an acute angle to the upper surface of the strip;

axis of the nail is at an acute angle tothe upper surface 7 the steps of:

providing a carpet nail comprising a length of metal nail wire having a bevelled face on each end, said faces at the nail to reforming the point on the upper end of the nail to form a sharper point; and

driving the nail farther into the strip to its final position.

References Cited in the file of this patent I UNITED STATES PATENTS 637,193 Woozley Nov. 14, 1899 712,569 Myers Nov. 4, 1902 2,504,987 Krah et a1. Apr. 25, 1950 2,806,243 Maex Sept. 17, 1957 2,821,714 Kent et a1. Feb. 4, 1958 2,846,712 Marlcman Aug. 12, 1958 

